The present invention is directed to an adaptor for attachment to a rotating work piece holder of a machining center. More particularly, the present invention is directed to an adaptor that is designed to clean the clamping surfaces of a number of associated work piece chucks using a pressurized fluid, such as pressurized air, water or coolant.
Computerized (i.e., CNC) machining centers are well known in the machining industry. Variations of such devices include, for example, vertical machining centers, horizontal machining centers and turning centers. CNC turning centers are essentially high-tech lathes that are operative to turn various components. Typically, turning operations in such turning centers follow preprogrammed numerical instructions, thereby requiring little if any operator intervention. CNC turning centers may further automate the turning process by providing for automatic part loading and unloading, etc. Lathes are, of course, also well known in the industry, and are generally turning centers absent computer control.
CNC turning centers and other lathes typically include a work piece holder that is attached to a rotating spindle. A work piece is securely affixed to the work piece holder during the turning operation. Various techniques may be employed to secure a work piece to a work piece holder. A common technique, and the technique of interest herein, includes the use of a number of moveable chucks that are associated with the work piece holder. Such chucks are typically moveable in a direction transverse to the longitudinal axis of the spindle. In this manner, a number of such chucks can be located about the periphery of a work piece and used to exert an inward clamping force on the work piece—thereby securing the work piece to the work piece holder during a turning operation.
During a turning operation, considerable heat can be generated between the work piece and the cutting tool(s) used to shape the work piece. Consequently, coolant is typically applied to a work piece and/or cutting tool during the cutting operation. When turning is performed on an exterior portion of the work piece, the application of coolant is commonly accomplished via one or more nozzles that are typically repositionable as needed. In the case of turning along an interior bore, however, access thereto by such nozzles is not always possible. As such, an adaptor may be affixed to the end of the work piece holder (or to a part locator mountable to the work piece holder) to apply coolant to an interior portion of the work piece as needed. Excess coolant typically flows off of, and/or out of, the work piece and into a collection device during a turning operation.
As would be apparent to one skilled in the art, numerous shavings and chips (collectively referred to hereinafter as “chips”) of work piece material are generated during a typical turning operation. These chips typically collect on various parts of the turning center, including the chucks or other mechanisms employed to retain the work piece on the work piece holder. When a work piece has a bore or other interior void(s), chips may collect therein as well. Consequently, turning centers commonly employ various cleaning functions to remove such chips. For example, a turning center may utilize one or more of a coolant flush, air blow and/or high-speed rotation operation in order to effectuate chip removal.
It has been found, however, that even after using one or more of such cleaning techniques, chips sometimes remain on the chucks of a work piece holder. The chips are believed to remain for several reasons. First, during a high-speed spinning operation, generated centrifugal forces actually press the chips against the clamping surfaces of the chucks, thereby making ejection thereof difficult. Dried or partially dried coolant may also tend to adhere chips to the clamping surfaces of the work piece chucks. Further, current adaptors for emitting pressurized fluid fail to actually direct a flow of fluid at the chuck surfaces. As such, chips may remain on the clamping surfaces of work piece chucks, even after a cleaning operation has been completed.
The presence of such chips can interfere with the clamping of a new work piece to the work piece holder and may also interfere with a subsequent turning operation or other machine functions if dislodged. Further, clamping a work piece when chips are present on one or more of the work piece chuck clamping surfaces can result in the work piece being out of position. Consequently, subsequent machining operations may produce a work piece that is dimensionally inaccurate (e.g., that may not meet runout tolerances, etc.).
Therefore, what is needed is a device and method that can provide for a more thorough and precise cleaning of work piece holder elements—particularly, work piece chucks. An adaptor of the present invention and its method of use satisfies these needs.